The mandarin orange, also known as the mandarin, is the fruit of the Citrus reticulata, a shrub 3 to 6 meters high, originating in Asia and whose cultivation only appeared in Europe as from the 19th century. Like all members of the Citrus genus, it is part of the Rutaceae family, which includes citrus-producing trees. The cultivation of mandarins is one of the oldest. It is one of the most marketed and popular citrus fruits (DOSOKY & SETZER, 2018).
In phytotherapy, the essential oil from the peel, leaves and flower bud is used. The essential oil from the peel is rich in monoterpenes such as limonene and ϒ-terpinene (NJOROGE & al., 2005 ; FAYED & al., 2009). As for the leaf essential oil, it is rich in sabinene and γ-terpinene (KIRBASLAR & KIRBASLAR, 2006).
Orally administered essential oil from the peel induces anxiolytic and sedative effects in individuals subjected to various tests related to generalized anxiety and obsessive-compulsive disorders. In addition, it increases the duration of sleep induced by ether inhalation. These effects are not associated with motor deficits in treated animals (GARGANO & al., 2008).
The essential oil from the mandarin leaf and peel has a greater anti-radical activity than that of orange leaf and that of geranium (DONGMO & al., 2008 ; FAYED et al., 2009 ; YI & al., 2018). In addition, using the lipoxygenase enzymatic method, the authors demonstrated that it has high anti-inflammatory activity (DONGMO & al., 2008).
It would seem that these radical scavenging and anti-inflammatory activities are explained by its high d-limonene content (YU & al., 2017 ; DOSOKY & SETZER, 2018).
In mice receiving a high-fat diet, daily supplementation with mandarin peel extracts improved glucose tolerance and insulin resistance. Moreover, in two models of non-alcoholic steatohepatitis, this supplementation improves lipid profiles, reduces oxidative stress, limits hepatic steatosis and decreases inflammatory factors. This is interesting because excessive lipid deposition, oxidative stress, and inflammation of liver tissue are considered crucial inducers of nonalcoholic steatohepatitis (KE & al., 2020).
Essential oil from mandarin leaf exhibits anti-cancer activity associated with its antioxidant activity. In particular, it inhibits the proliferation of human promyelocytic leukemia cell lines HL-60 and NB4, presenting LC50 values of 85.05 µg/ml in the NB4 line and 105.73 µg/ml in the HL-60 line (FAYED & al., 2009).
Essential oil from madarin peel inhibits the growth of several bacteria including Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis and Staphylococcus aureus (YI & al., 2018).
In addition, it exhibits an antimycotic effect on several fungi including Penicillium italicum, P. digitatum and Aspergillus niger. It disrupts the integrity of their cell membrane and causes their components to leak out. This antifungal activity is associated with different constituents such as citronellol, octanal, limonene, citral, decanal, nonanal, β-pinene, linalool, γ-terpinene, and α-terpineol (TAO & al., 2014 ; WU & al., 2014).
